Statistics Exercise I: Descriptive statistics

These weekly exercises provide an opportunity for you to understand and apply statistical methods and analysis.

#1. Given the following values of the mean and median, state the likely shape of the distribution:

(a) mean = 4, median = 4 _______________

(b) mean = 12, median = 2 _______________

(c) mean = 8, median = 18 _______________

(d) mean = 6, median = 14 _______________

(e) mean = 10, median = 3 _______________

(f) mean = 8, median = 8 _______________

#2. IQ scores have a mean of 100 and a standard deviation of 15. What percentile corresponds to an IQ score of 115? Explain the steps you took to find the percentile.

#3. Which measure of central tendency would you use for the following variables (mean, median or mode)? Explain your choice.

Gender: _____

Class rank at a college: _______

Age of high school students: _____

A skewed income distribution (90% with incomes under $150K; a few with incomes of several million): _____

Use SPSS and the data file found in syllabus resources (DATA540.SAV) to answer the following questions. Round your answers to the nearest dollar, percentage point, or whole number.

#4. What is the mean annual income (INC1) of the participants?

$43,282  $72,133  $47,113  $34,282

#5. What percent of the participants are married (RELAT)?

28% 33% 51% 59%

#6. What is the modal level of relationship happiness (HAPPY)? Mixed Happy Very Happy Cannot be determined

#7. What is the median income of the participants’ partners (INC2)?

$24,212 $28,945 $32,000 $48,975

#8. What percent of the participants are age 51 or older?

4% 5% 7% 10%